GWINNETT COUNTY, Ga. (KDKA) — Investigators in Georgia say a teenager and her boyfriend killed her grandparents and lived with their bodies for days.

According to CBS News, a detective testified that after bludgeoning and stabbing her grandparents to death, Cassandra Bjorge and her boyfriend Johnny Hiro Rider stayed in the home smoking marijuana and partying with friends while Randall and Wendy Bjorge’s bodies laid upstairs.

Bjorge, 17, and Hiro, 19, are charged with murder in the deaths of Wendy and Randall Bjorge.

Police say the couple used a tire iron, hammer, baseball bat and knives to kill the grandparents. They then caulked doors inside the home to attempt to keep the smell of the bodies inside.

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Gwinnett County Homicide Detective Dave Brucz reportedly testified Wednesday that Bjorge confessed to the crime but Rider has not spoken to police.

“Johnny began to attack the grandfather,” testified Brucz, “Cassie then said that she basically had a surge of energy. She then dragged her grandmother into her grandfather’s bedroom. She was duct-taped.”

Police say Bjorge and Rider planned to kill more people, including Rider’s family and Bjorge’s mother, but that Rider backed out of the plan. They are however, accused of trying to kill Rider’s sister and her boyfriend.

Rider’s sister escaped, and that led to the teens’ capture more than a week after the grandparents’ murders.

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